A hydraulic jack commonly has its opposite ends in fluid communication with a control valve which is selectively positionable to direct pressurized fluid from a pump to one end of the hydraulic jack with the fluid exhausted from the opposite end being returned to a tank through the control valve. Normally, the size of the control valve is selected to match the pump output. However, one of the problems frequently encountered with such an arrangement is that the piston rod of the hydraulic jack is attached to one side of the piston and creates unequal actuating areas and displacement volumes on opposite sides of the piston. Thus, when actuating fluid is directed to the rod side of the piston for retracting the hydraulic jack, a substantially greater volume of fluid is exhausted from the head end side. Occasionally, the difference in volume is of a magnitude that the control valve and lines will not efficiently handle the larger volume of exhausted fluid. This creates a back pressure in the exhausted fluid thereby slowing down retraction of the hydraulic jack.